Studies are planned of hemodynamics, metabolism, and respiratory function in man and in laboratory animals in shock. For man, a team has been established which will record data at the bedside from patients in shock from a variety of causes, including hypovolemia, sepsis, cardiac disease, pulmonary embolism, and others. Adjuncts to the therapy of shock in man are being evaluated, including the effects of controlled hypotension in selected cases of continuing hemorrhage, influences of change in hematocrit on viscosity of blood and rates of bleeding, effects of catecholamines, glucagon, and alpha-adrenergic blockade on the heart and peripheral circulation, and effects of adrenal steroids in clinical shock. Hypotheses derived from observations in man will be tested in the experimental laboratory. Observations being made in the experimental laboratory include studies of the effects of hematocrit on viscosity, flow rates, and bleeding rates in vitro and in experimental animals, hemodynamics of inflammation, changes in purine metabolism in shock, and morphologic changes of the brain in severe hemorrhage.